We performed molecular and morphological analyses to determine generic limit of the genus Aulacorthum including several species with controversial taxonomic histories. The sequences of four mitochondrial genes, COI, COII, srRNA and lrRNA, and one nuclear gene, EF1a, implied that Aulacorthum is not monophyletic, with Aulacorthum magnoliae and Aulacorthum nipponicum forming a clade that is not sister to other currently recognized Aulacorthum species. Morphometric analysis based on 20 morphological characters also showed that A. magnoliae and A.nipponicum exhibited morphological characteristics distinct from congeneric species. Based these results, we propose a new genus, Neoaulacorthum ge. n. for A.magnoliae and A.nipponicum.

The functional response and spatial distribution of parasitoid may be useful for understanding host-parasitoid dynamics because information on these will give knowledge of the host-parasitoid interaction, which could lead to the development of strategy for biological control of insect pests. The functional responses of A. asychis on the green peach aphid and potato aphid was investigated in eggplant leaf-disc arena. As a result, among the three types of functional response, type III best described the A. asychis response to the aphid densities, according to the Bayesian Information Criterion (BIC). Functional response and spatial distribution of A. asychis on green peach aphid, Myzus persicae, was investigated on 5x5 eggplants in the net cage. After M. persicae were inoculated uniformly at the densities of 1, 3, 6, 9 and 12 (per plant) on upper, middle and lower leaves of each 25 eggplants, one mated female of A. asychis was introduced on the central eggplant. Each aphid density was duplicated. A. asychis showed a type II functional response different from that estimated on the eggplant leaf-disc arena. Although the initial distribution of the aphids in the 25 eggplants was uniform vertically and horizontally, the aphids became gradually concentrated on the upper leaves of eggplants, so did immature A. asychis.

To investigate resistance of Myzus persicae, which is resistant to etofenprox belonging to pyrethriods, to other insecticides, fenpropathrin and thiamethoxam, mortality and LC₅₀ values for these two insecticides against the etofenprox-resistant and -susceptible populations were obtained and EPG analysis for feeding behaviors of thiamethoxam or fenpropathrin treated and non-treated M. persicae was conducted. For fenpropathrin, mortality after 48 h treatment was 28 and 29%, respectively for the resistant and susceptible population. The LC₅₀ value was 193.15 and 93.46 ppm, respectively. For thiamethoxam, mortality after 48 h treatment was 87 and 57%, respectively for the resistant and susceptible population. The LC₅₀ value was 3.17 and 30.34 ppm, respectively. There was no significant difference in feeding behavior between fenprorpathrin treated and non-treated M. persicae. They showed a continuous feeding pattern. However, contact signal frequency increased in the thiamethoxam treated M. persicae 1 hour after treatment and significant difference was shown.

This study was performed to investigate the correlation between changes of feeding behavior of green peach aphid, Myzus persicae and residual effect of an insecticide, Pyrifluzuinazon, using EPG technique. Pyrifluquinazon was showed the insecticidal activity until three days (72h) after treatment, and the activity was high in nymph than adult of GPA. There was no difference among treatment methods. Lethal sign was observed the slimed the abdomen of GPA after 3 days that rises the insecticidal activity, and dieㅇ as being sticked and/or pulled out the needle. Residual efficacy from 1, 3, 5, 7 to 20 days after treatment, insecticidal activity was showed 70% in 50 ppm, recommended concentration, until 5 days. And waveforms relating to non-probe time and phloem phase time using EPA, feeding inhibition efficacy was showed during 5 days after treatment, but showed similar level with control after 13 days. These results show that the change of feeding behavior of GPA is correlated with the change of residual effect of pyrifluzuinazon.

The performance of herbivores is directly determined by the quality of host plants which changed rapidly with abiotic environment. Elevated CO2-induced nitrogen decreases in plant foliage reduces the growth of chewing herbivorous insects. In contract, although aphids had species-specific response to elevated CO2, it was still considered that aphids’ population have been found to be the only feeding guild to respond positively to elevated CO2. Few studies of elevated CO2 effects on sap-feeding aphids can explain why aphids would make its success under elevated CO2 environment. Plant re-allocates the carbon and nitrogen in tissue under elevated CO2, and in turn alters structure of plant leaves, reduces the amino acid content of phloem sap and increased secondary metabolites of plant. However, it is difficult and unreasonable to predict the general response of aphids to elevated CO2 by using a single plant component. Instead, it is more likely that, in terms of interacting with host plant, aphids are trying to overcome the disadvantages of elevated CO2 and maximum their fitness under elevated CO2 environment. It may provide several cues to explain why individual species will achieve success under future elevated CO2. The present paper reviews recent studies of elevated CO2 effects on aphids and discusses the effects of elevated CO2 on aphid performance on crops using cotton and cereal aphids as examples. Further work examining induced defense of plant against aphids under elevated CO2 will contribute largely to current knowledge.

Aphid is relatively young group among insects, which radiated contemporaneously with the host plants in angiosperm. Based on recent molecular phylogenetic studies, the tribe Aphidini has been strongly suggested as a primitive group sister to two other tribes, Macrosiphini and Pterocommatini, in the subfamily Aphidinae which is most diversified aphid group. These ideas have been proposed due to the phylogenetic relationships between the groups and the relatively simple morphological characters. Our study is aimed to confirm the evolutionary process of this primitive group in order to understand the diversification of the modern aphids. Firstly, we obtained the phylogenetic relationships for 59 ingroup species plus 10 outgroup species (6 macrosiphine species, 1 hormaphidine species, and 3 adelgids) based on the combined sequences (2,899 bp) of three mitochondrial genes (COI, COII, CytB) and one nuclear gene (EF1α). The optimal tree topology is obtained by the ML analysis in GARLI 0.95b with Kishino-Hasegawa and Shimodaira-Hasegawa tests in PAUP*4b10, and the posterior probabilities on each node were estimated by MrBayes 3.1.1 under the best fit model (GTR+I+G) tested by MrMODELTEST 3.0. Then, the node ages of the obtained tree were calibrated using the relaxed-clock model implemented in BEAST 1.4.8 and its package programs based on one node fixation of 150 MYA (million years ago) for Aphididae+Adelgidae, and two node constraints as 80-100 MYA for Aphididae crown and 50-70 MYA for Aphidinae crown according to the fossil related publications. As results, we found four major facts on their evolution: 1) Aphidini radiated from the early Eocene in the Tertiary, 2) however, most lineages rapidly radiated during the late Eocene, 3) common ancestor of the subtribe Aphidina maybe fed on herbs or shrubs in asterids, 4) host alternation trait was lately acquired on Rosaceae- or Rhamnaceae-feeding aphids.

For the comparing of mortality of the resistance and susceptible population of Myzus persicae, etofenprox was treated in the recommended concentration of 200ppm. Mortalities of resistance population were 16.7 and 36.7%, and susceptible population were 86.7 and 86.7% after 24 and 48 hours treatment, respectively. For the detect of cross resistance to other pyrethroids, 6 pyrethroids were examined. Mortalities of susceptible and resistance populations were 90 and 31% to deltamethrin, 92 and 23% to lambda cyhalothrin, 81 and 14% to cypermethrin, 70 and 20% to α-cypermethrin, 29 and 28% to fenpropathrin, 84 and 29% to fenvalerate, respectively. It was showed that resistance populations were generally resistive to other pyrethroids. On the other hands, for recognized ecological characteristic of M. persicae susceptible and resistance populations life table was tested on the pepper leaves in the petri dish and on the plant in the pot. This results were showed that intrinsic rate of increase (r<SUB>m</SUB>), net reproduction number (R₀) and generation time in day (T<SUB>c</SUB>) were significantly different between two population in both tested. However, life span and reproduction period were slightly different between them. Otherwise, feeding behaviors were tested using EPG technique with non- and treated etofenprox. First potential drop time of susceptible and resistance population was 73.5 and 257.9 sec with non-treated and 93.3 and 1076.2 sec after treated, respectively. Electrical probing signals were 8.2 and 48.8 times with susceptible and resistance individuals after treated etofenprox, respectively. It was supposed that the resistance is more probings than susceptible population. After treated, total feeding time have more 6,728.9 sec on resistance than 965.5 sec on susceptible population. So, total non penetration time of susceptible population was 3,000 sec longer than resistance population.

The soybean aphid, Aphis glycines Matsumura 1917, is well known as a soybean pest in the world. Recently, it has been introduced to North America causing serious damage in U.S. As a cooperative research with USDA-ARS, we have investigated A. glycines in soybean fields, and also examined the colonies on the overwintering host Rhamnus davurica in order to find its natural enemies. It was generally reported that A. glycines has host alternation between the soybean, Glycine max (summer host) and the Dahurian buckthorn, Rhamnus davurica (winter host) in East Asia. However, it was very difficult to identify the soybean aphid, A. glycines, from R. davurica due to the co-existance of at least three Aphis species and the seasonal polymorphisms of each species (e.g, gynopara, ovipara, and male). For species identification, we tested 3 molecular markers, mitochondrial COI, COII, and nuclear EF1α, for 14 collected samples (7 samples from G. max and 7 samples from R. davurica). As a result, we found two different species, A. gossypii and other Aphis sp., are mixed together with A. glycines on R. davurica. We report the biology of A. glycines in Korea, and present species identification using molecular phylogenetic approach.

Adult longevity and fecundity of the foxglove aphid, Aulacorthum solani Kaltenbach, were studied at 12.5~25℃ with 60~70% RH under 16L:8D and the results were put together to build a life table. The longevity of foxglove gradually increased with decreasing temperature below 25℃. Also total fecundity increased with decreasing temperature and highest fecundity was 74.1 nymphs per female at 15℃. However, daily fecundity increased with increasing temperatures up to 20℃ showing 2.9 nymphs per day and thereafter decreased. Net reproduction rate (R₀) was highest of 58.7 at 15℃. The intrinsic rate of increase per day (r<SUB>m</SUB>) and the finite rate of increase per day (λ) were highest of 0.27 and 1.32, respectively and the doubling time (Dt) was shortest of 2.52. the mean generation time (T) was 10.99 at 22.5℃.

The development of Aulacorthum solani (Kaltenbach) was studied at temperatures ranging from 12.5 to 27.5℃ under 65±5% RH, and a photoperiod of 16:8 (L:D). Mortality of 1st~2nd nymph was higher than that of 3rd~4th nymph at the most temperature ranges whereas at high temperature of 27.5℃, more 3~4th nymph stage individuals died. The total developmental time ranged from 16.9 days at 12.5℃ to 6.6days at 22.5℃, suggesting that higher the temperature, faster the development. However, at higher temperature of 25℃ the development took 7.4 days. The lower developmental threshold temperature and effective accumulative temperatures for the total immature stage were 0.08℃ and 162.8 day-degreeslated development. The nonlinear shape of temperature rewas well described by the modified Sharpe and DeMichele model. When the normalized cumulative frequency distributions of developmental times for each life stage were fitted to the three-parameter Weibull function, attendance of shortened developmental times was apparent with in 1~2nd nymph, 3~4th nymph, and total nymph stages in descending order. The coefficient of determination r² ranged between 0.86 and 0.91.

Fifty potato cultivars were screened for potato aphid, Macrosiphum euphorbiae Thomas infestation degree in the field. Aphid honey dew secretion and contents of foliar substances (glycoalkaloids, total nitrogen, Ca, K and Mg) of the cultivars were measured in the laboratory to analyze the correlation between infestation degrees and those factors. The number of aphids ranged from 4.1 to 31.4 per five leaves. The lower density (less than 5 aphids) was found on cvs. Jidose, Recent, and Sebago. The aphid secreted highest (40.3 droplets) and lowest (15.7 droplets) honeydew on cvs. Jopoong and Anco, respectively. Degree of infestation is positively correlated to glycoalkaloids and total nitrogen contents of the potato leaf.

The turnip aphid is a worldwide pest, damaging mainly to crucifers. In order to understand the life parameters of Lipaphis erysimi for the eventual goal of control, the developmental periods, survival rates, lifespan, and fecundity of the species were investigated under five temperature regimes (15℃ - 35℃). Furthermore, the efficacy of several environment-friendly agricultural materials (EFAMs) that are on the market was subjected to test in order to obtain further accurate information. The developmental period of the turnip aphid nymph was longest at 15ºC as 16.9 days, shortened as temperature goes up to 25ºC (5.4 days), and then somewhat increased at 30ºC (5.9 days), suggesting that the most efficient temperature for nymphal development could be around 25ºC. Mortality of the nymphal turnip aphid was obvious at 35ºC, whereas it was minimal at other temperature schemes. The longevity of adults shortened as temperature goes up to 30ºC. In particular, the maximum lifespan for adults continued for 55 days at 15ºC, but shortened to 21 days at 30ºC. The total fecundity per day was 35.7 at 15ºC, 81 at 20ºC, 64.2 at 25ºC, and 6.6 individuals at 30ºC, showing the highest fecundity at 20ºC. After the turnip aphids were successfully stabilized in indoor environment the insecticidal activity was tested and mortality was determined 12, 24, 36, and 48 hrs after EFAMs are treated. Several on-the-market EFAMs showed more than 90% of insecticidal activity within 24 hrs or 48 hrs, but a few showed less than 90% activity, signifying importance of selection of proper EFAMs.

As the results achieved by the evaluation of toxicities on an aphid parasitoid, Aphidius colemani by 79 pesticides registered as horticultural pesticide and 4 adjuvants for pest control, 6 insecticides including a-cypermethrin, 13 fungicides including metalaxyl-M+mancozeb and 4 acaricides including bifenazate showed low toxicity against A. colemani adult. Low toxicity was showed in all the 4 adjuvants as well. In residual toxicity test from 40 pesticides which showed toxicity more than 50%, A. colemani was safe from 11 pesticides from the 3th day after treatment, 7 pesticides from the 5th day after treatment and 14 pesticides from the 7th day after treatment, respectively. But, chlorpyrifos-methyl, diflubenzuron+chlorpyrifos, etofenprox+diazinone and imidachloprid+chlorpyrifos showed high toxicities reaching 100%, 97.7%, 100% and 100% respectively, even from the 7th day after treatment. To evaluate the control effect by A. colemani against Myzus persicae in a greenhouse, A. colemani was released at parasitoid versus aphids rates of 1:50 and 1:100 when the population of M. persicae was 50 per plant. After release, aphids population remained steady for 20 days after release at the level of around 60 aphids per plant During the investigation, insecticides for thrips control and fungicides for powdery mildew control were treated, but didn"t affect the mummy forming of A. colemani. It may be suggested from these results that the selected insecticides, fungicides, acaricides and adjuvent could be incorporated into the integrated M. persicae management system with A. colemani on greenhouse cultivation.

복숭아혹진딧물의 섭식행동을 관찰하기 위해, 고추, 무, 배추, 가지, 참외 등 5종류의 기주식물에서 EPG기술을 이용하였다. 복숭아혹진딧물의 구침이 식물체 표면에 접촉된 후 전기적 연결이 일어나기까지 소요되는 시간과 맨 처음 potential drop이 일어나기까지 소요된 시간, 구침의 세포간극내에서의 활동에 의하여 일어나는 potential drop의 수, 전기적 연결신호가 나타난 시점부터 체관부를 섭식하는 순간까지 소요된 시간 등을 조사한 결과 Potential drop 수에서는 기주들 사이에 유의성 있는 차이를 나타내었다. 그러나 나머지 요인에서는 기주식물들 사이에 큰 차이를 보이지 않았지만, 참외나 배추보다는 고추, 무, 가지에서 즘 더 기주선호성과 관련된 섭식패턴들을 확인할 수 있었다.

복숭아혹진딧물(Myzus persicae )의 성충 발육과 산자수를 , 상대습도 60-70%, 광주기 16L:8D 조건에서 조사하고 생명표를 작성하였다. 복숭아혹진딧물 성충은 까지 수명이 일로 온도의 상승에 따라 성충기간이 짧아졌으며, 산자수는 에서 40.8마리로 최고치를 보였으나 까지 산자수 차이에 유의성이 인정되지 않았다. 다만 에서는 8.4마리로 고온에 영향을 받은 것으로 보인다. 또한 복숭아혹진딧물 성충의 일일 산자수는 에서 5.1마리였고, 와 에서는 모두 2.8마리로 온도가 높거나 낮아지면서 일일산자수가 적어졌다. 온도별 총 산자수를 이용하여 작성한 산자 모형을 보면 에서 51.0마리로 최고값을 보인다. 또한 약충 발육시 사망률과 성충 수명, 산자수를 이용하여 생명표를 작성하였는데 복숭아혹진딧물은 Ro가 에서 36.5, 은 0.4, Dt는 1.6, 기간증가율은 1.5, 세대기간은 8.1로 가 복숭아혹진딧물 증가에 가장 적합한 온도로 나타났다.